CMS 4GB (1X4GB) DDR3 12800 1600MHz Non ECC DIMM Memory Ram Upgrade Compatible with Dell® Optiplex 3020 Mt/Sff - A73 at Amazon.com
Dell OptiPlex 3020 Small Form Factor PC, 3.2GHz Intel i5 Quad Core Gen 4, 4GB RAM, 500GB SATA HD, Windows 10 Home 64 bit, 19" Screen (Renewed) | McClatchy
OFFTEK 8GB Replacement Memory RAM Upgrade for Dell OptiPlex 3020 (Small Form Factor) (DDR3-12800 - Non-ECC) Desktop Memory at Amazon.com
Optiplex 3020 SFF Graphics Card Upgrade - Dell Community
Optiplex 3020 graphics card upgrade - Dell Community
Dell OptiPlex 3020 MT – Specs and upgrade options
How to upgrade the DELL 3020 Memory (RAM) - YouTube